|
 A
lone bolt strikes out. The lower parts of a thundercloud
tend to accumulate negative charges, which induces a
positive charge on the ground. When the voltage
difference exceeds the insulating capacity of the air, a
lightning stroke completes the electrical circuit and
discharges the buildup of static electricity. A strong
but localized storm in late August 1997 is backlit by
the setting Sun near the Silverbell Mountains northwest
of Tucson, Arizona. Equipment: Kiev Model 80 Medium
format SLR; Fuji Velvia film. Brian Mayeaux
Lightning, being the flash
in the sky
that it is, serves as both the natural lighting and the
focal point to some wonderfully stormy compositions.
Although daytime lightning photography is quite a
challenge, capturing the flashes in a dark sky is fairly
easy.
Equipment.
A
35 mm SLR camera with a bulb (B) setting for long
exposures, or a digital or video camera with controls
for low light settings; tripod; shutter release cable to
avoid camera movement; and slow film of 100 or 200 ISO
completes a basic setup. Any lens from 28mm to 135 mm
works well; a zoom lens may isolate too much of the
storm causing you to miss strikes outside your field of
view.
 Composure.
The most picturesque thunderstorms are large, active and
isolated. Storms that are downpouring, dying or simply
too far away, and those with mostly intracloud
lightning, simply won’t produce satisfying results.
Avoid extraneous lights from the Moon, structures, cars
and other sources. Including at least a portion of the
horizon adds visual interest.
Safety.
There’s no way around it; lightning photography is
risky. But you can reduce some of that risk by staying
dry and avoiding hilltops, open fields, bodies of water,
nearby fences and metallic paths, power lines and trees.
(See the Personal Lightning Safety Tips.) Plan ahead for
emergency shelter. Shooting from your car with your
camera mounted on a window clamp is a relatively safe
option.
Technique.
Aim at the storm, focus on infinity, set the f-stop,
open the shutter, wait for a strike, close the shutter,
advance the film; repeat. If no strikes appear within 45
seconds or so, your foreground may be overexposed when
one does occur; advance the film for another try. If
your storm is moving quickly, limit the length of your
exposures to avoid blurring motions. On the other hand,
keeping the shutter open during a particularly active
period may result in spectacular multiple-stroke images.
Because distant lightning is not as bright as closer
strikes, your f-stop must vary according to the
brightness. Bracketing your shots will increase your
chances of a perfect exposure, but, as a rule of thumb,
distant flashes (3-10 miles away) may call for apertures
of f/2.8 – f/5.6; close strikes (1-3 miles), f/11 –
f/16. (For strikes in the immediate vicinity, you’ll
never even hear the one that zaps you: flee!) ©
Tim Herd
 above,
left: Ribbon lightning occurs in strong wind blowing
perpendicular to the line of sight, spreading the
channel sideways as successive strokes follow it,
widening the observed flash. Taken from a dangerously
close range near Granite, Oklahoma, this series of
strokes display the classic ribbon effect on May
30, 2006. Hank Baker
right: Zigzagging
javelins repeatedly stab the ground in a red-tinted
barrage over Tucson. Warren Faidley |
